Subsequent Events (Details) - USD ($) $ / shares in Units, $ in Thousands						3 Months Ended					9 Months Ended
		Nov. 05, 2021	Oct. 15, 2021	Oct. 07, 2021	Jan. 25, 2020	Sep. 30, 2021		Sep. 30, 2020	Mar. 31, 2020		Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Feb. 13, 2019	Aug. 18, 2017
Subsequent Event [Line Items]
Common Stock, Par or Stated Value Per Share						$ 0.001					$ 0.001		$ 0.001
Stock Issued During Period, Shares, New Issues					5,290,000	7,852,900		0			7,852,900	5,290,000
Over-Allotment Option [Member]
Subsequent Event [Line Items]
Stock Issued During Period, Shares, New Issues					690,000
Senior Notes
Subsequent Event [Line Items]
Debt Instrument, Interest Rate, Stated Percentage														5.50%
Debt Instrument, Face Amount															$ 86,000
Common Stock
Subsequent Event [Line Items]
Stock Issued During Period, Shares, New Issues	[1]					7,852,900			5,290,000
Stock Issued During Period, Value, New Issues			$ 103,500			$ 141,303	[1]		$ 95,292	[1]
Subsequent Event [Member]
Subsequent Event [Line Items]
Dividend Per Share (USD per share)		$ 0.15
Declared date		Nov. 05, 2021		Oct. 07, 2021
Payment Date		Dec. 27, 2021
Record Date		Nov. 30, 2021
Stock Issued During Period, Shares, New Issues			5,750,000
Subsequent Event [Member] | Over-Allotment Option [Member]
Subsequent Event [Line Items]
Stock Issued During Period, Shares, New Issues			750,000
Subsequent Event [Member] | Common Stock
Subsequent Event [Line Items]
Dividend Per Share (USD per share)				$ 0.15
Payment Date				Nov. 26, 2021
Record Date				Oct. 29, 2021
Subsequent Event [Member] | Preferred Stock [Member]
Subsequent Event [Line Items]
Dividend Per Share (USD per share)				$ 0.421875
Payment Date				Nov. 01, 2021
Record Date				Oct. 18, 2021

[1] Net of underwriters' discounts and commissions and offering costs.